Many mobile devices, such as mobile phones or other portable electronics, include audio jacks and are configured to distinguish between a variety of external audio jack accessories using the baseband processor of the mobile device. However, using the baseband processor to distinguish between external audio jack accessories can utilize valuable general purpose input/output pins on the baseband processor, as well as memory and processor time. Further, because the baseband processor is responsible for many other important operations, distinguishing between external audio jack accessories using a separate detection circuit can improve the efficiency, both time and power, of detecting and identifying external devices.